Three states with vastly different electoral profiles are holding primary elections on Tuesday: Alabama, Maine and Texas.
The marquee contests include a Republican primary for Senate in Alabama in which President Trump is pursuing a personal vendetta; a Democratic primary for Senate in Maine whose winner will take on the only Republican from New England in Congress; and runoffs in Texas for the Democratic Senate nomination and two Texas House districts that are expected to be tossups in November.
Most of the polls in all three states will close at 8 p.m. Eastern time. Some early returns are likely to come in soon after that, but full results will take longer.
Here’s what to watch for:
The primary in Alabama could end Jeff Sessions’s political career.
In any other year, under any other president, Jeff Sessions is the kind of Republican who would have a clear shot at winning a Senate seat in Alabama. He is experienced and deeply conservative and has built up good will with voters over decades in public office. But a runoff election on Tuesday with Tommy Tuberville, a former college football coach and political newcomer, could be the end of a career in Republican politics that began when Mr. Sessions was still in college — and when most of Alabama voted Democratic.
Like most Republican primary contests, this one will be seen as a test of how tightly Mr. Trump retains a grip on his core supporters. He has endorsed Mr. Tuberville and repeatedly, angrily attacked Mr. Sessions, the former attorney general whose recusal from an investigation into Russian interference in the 2016 election helped prompt the appointment of Robert S. Mueller III as special counsel.
Mr. Sessions has always been the underdog. In the first round of voting in early March, he finished behind Mr. Tuberville — but by less than two percentage points. (Other candidates were in the race and no one received an outright majority, forcing a runoff election.) And Tuesday’s results will in part reveal whether Mr. Trump’s barrage of insults and pleas to Alabamians to reject his former ally — “not mentally qualified” and “a disaster who has let us all down” are just two of the more recent jabs — have helped make Mr. Sessions appear to be too much of a risk to voters. Public and private polls have shown Mr. Tuberville with a comfortable lead.
Or a loss for Mr. Sessions could be about something else entirely: voters who are looking for a new kind of leadership in Washington and who have qualms about sending back a 73-year-old whom they have already elected to the same Senate seat four times.
Alabama voters have rejected Trump’s advice before. Twice.
Alabama is definitely Trump country. And Mr. Tuberville has no doubt benefited from the president’s many endorsements. But Alabama voters also have a mind of their own when it comes to electing senators. In fact, the only reason Mr. Sessions is running is that Mr. Trump’s last two endorsements didn’t pan out the way he had hoped.
After Mr. Sessions was confirmed as attorney general in 2017 and left the Senate seat open, it was filled by Luther Strange, a former state attorney general who was appointed by the governor. Mr. Trump endorsed Mr. Strange when he had to stand for re-election later that year, viewing him as a loyal soldier and an ally in the Senate.
But a populist backlash against Mr. Strange, who faced ethics questions in Alabama about how he had obtained the Senate appointment, allowed Roy S. Moore to win the Republican nomination. Mr. Trump then endorsed Mr. Moore, a former Alabama Supreme Court justice who gained national notoriety after placing a huge stone replica of the Ten Commandments at the state judicial building.
Mr. Trump stood by his endorsement even after several women stepped forward to accuse Mr. Moore of fondling and harassing them when they were teenagers and he was a prominent local lawyer.
Mr. Moore lost the race after other Republicans, most notably the state’s senior senator, Richard Shelby, said he could not vote for the former judge.
All eyes will be on Doug Jones.
Mr. Moore’s scandal gave Alabama its first Democratic senator in a generation: Doug Jones. And after Tuesday, when his opponent is determined, his race will get a fresh look. Mr. Jones is in the most difficult position of any Senate Democrat up for re-election this year. In 2016, Mr. Trump carried Alabama by almost 30 points, making it hard for any Democrat to do well statewide, even if the president’s popularity continues to slide.
Mr. Jones’s victory in 2017 was widely seen not as evidence of a resurgent Democratic Party in a deep red state, but rather as a reflection of how beatable Mr. Moore was once the allegations of sexual abuse surfaced.
Mr. Jones — the lone Democrat representing the Deep South in the Senate — has tried to appear deliberative and fair-minded as he balances his personal opposition to the president with the feelings of the majority of his constituents. But his record, which includes a vote to remove Mr. Trump from office after his impeachment trial, will be a difficult sell with many voters.
Texas voters will choose a Democratic Senate nominee, and House seats are up for grabs.
Back in December, the Senate Democrats’ campaign arm waded into the Texas primary, endorsing M.J. Hegar over a field of candidates. Now Ms. Hegar, a former Air Force helicopter pilot who narrowly lost a 2018 bid for the House, faces a run-off against Royce West, a state legislator vying to become the first Black senator from Texas.
The winner will face Senator John Cornyn, a three-term incumbent who is the second-ranking Senate Republican and will be a heavy favorite in the general election.
We’ll also be watching two congressional runoffs in Texas: one for Republicans in the 22nd District, and one for Democrats in the 24th District. Both seats have been solidly red in the past but are expected to be competitive in November, because the Republican incumbents are retiring.
The 22nd District, which is in the Houston area and represented by Congressman Pete Olson, is home to a bitter race between Troy Nehls, the Fort Bend County sheriff, and Kathaleen Wall, a conservative activist. Mr. Nehls was far ahead of Ms. Wall in the first round of voting in March, but did not reach the 50 percent threshold needed to avoid a runoff.
Ms. Wall has been running ads accusing Mr. Nehls of failing to combat human trafficking in Fort Bend County, which advocacy groups say is a serious problem there. Mr. Nehls has called the allegation “an absolute lie.”
The winner will face the Democratic nominee, Sri Preston Kulkarni, who narrowly lost to Mr. Olson in 2018.
In the 24th District — a suburban stretch between Dallas and Fort Worth that is represented by Congressman Kenny Marchant — the Democratic candidates are Kim Olson, an Air Force veteran, and Candace Valenzuela, a former school board member who would be the first Afro-Latina member of Congress.
Ms. Olson, who ran for Texas agriculture commissioner in 2018, has advertised her 25 years of military service and the fact that she was part of the first generation of female fighter pilots. Ms. Valenzuela, by contrast, has emphasized her personal connections to the district and her difficult childhood; she grew up poor and became homeless after her mother left an abusive relationship.
Ms. Olson finished more than 10 percentage points ahead in the first round of voting in March, but Ms. Valenzuela’s supporters — who include Senators Elizabeth Warren of Massachusetts, Kamala Harris of California and Cory Booker of New Jersey; the former housing secretary Julián Castro; and Representative John Lewis of Georgia — think the race has shifted.
The winner will face the Republican nominee, Beth Van Duyne, a former mayor of Irving, Tex.
Who will be the Democrat to run against Susan Collins in Maine?
In the state’s Democratic primary for Senate, Sara Gideon, the speaker of the State House of Representatives, is viewed as the front-runner against two progressive challengers, Betsy Sweet, a lobbyist, and Bre Kidman, a lawyer. The race has drawn intense national focus because the winner will face Senator Susan Collins, who has become a reviled figure among national Democrats.
Although Ms. Collins is a moderate in her party who has long enjoyed bipartisan support in representing Maine in the Senate since 1997, her reluctance to forcefully push back against Mr. Trump has sent her approval ratings plummeting at home. Her vote to confirm Justice Brett M. Kavanaugh to the Supreme Court further angered liberals.
Ms. Gideon has already raised $23 million, a record sum for a Maine race, thanks to donors nationally who see her as the key to a Democratic takeover of the Senate. Ms. Gideon has staked out positions on health care and the environment in line with former Vice President Joseph R. Biden Jr., the presumptive Democratic nominee. Her two rivals, who champion more sweeping policies such as “Medicare for all,” have struggled to raise money.
Recent polls have shown Ms. Gideon with a narrow lead over Ms. Collins.
Reid J. Epstein contributed reporting.